Multi-subscriber warning system

Abstract

A multi-subscriber warning system can, in instances where emergencies are impending, apply ringing current to the "ring" lines of one party systems, to the "ring" lines of "ring" two party systems, and to the "tip" lines of "tip" two party systems. Those ringing signals will actuate the "ringers" of all instruments which are not in use, and will cause a buzzing sound in the reproducers of all instruments which are in use. Further, if a subscriber hears the "ringers" and raises the receiver from the cradle, a buzzing sound will be heard; and then the ringing sound will resume when the receiver is placed on the cradle. Conversely, if a buzzing sound is heard by a subscriber using the instrument, a ringing sound will be heard when the instrument is placed on the cradle; and the buzzing sound will resume when the receiver is again removed from the cradle. The duration and number of ringing sounds can be varied; and preferably will be different from the normal ringing sounds used to "call" a subscriber.

What I claim is: 
     
       1. A multi-subscriber warning system which utilizes the line pairs and instruments of a telephone system to provide a warning to subscribers whether those subscribers are using, or are merely within earshot of, their telephone instruments and which does not, at any time, interrupt or interfere with the normal continuous connections of said line pairs to the line equipment of said telephone system and which comprises a source of ringing current, a plurality of contacts that are connected to the ring-initiating conductors of said line pairs to serve as signal-injecting contacts for said ring-initiating conductors, a manually-set, subscriber-selecting, connecting means that is connected to said plurality of contacts to select predetermined contacts of said plurality of contacts through which said source of ringing current can supply a warning to the line pairs to which said predetermined contacts are connected, means that normally isolates said manually-set, subscriber-selecting, connecting means, and hence said predetermined contacts of said plurality of contacts, from said source of ringing current to normally keep said predetermined contacts from passing current and also to normally keep said predetermined contacts from having a detectable effect upon the operation of said telephone system, and said isolating means selectively connecting said source of ringing current to said predetermined contacts of said plurality of contacts via said manually-set, subscriber-selecting, connecting means and thereby connecting said source of ringing current to said ring-initiating conductors of said selected, predetermined line pairs to enable said source of ringing current to create a warning sound in the receivers of the telephone instruments that are connected to said selected, predetermined line pairs and that are in use and to actuate the "ringers" of the telephone instruments which are connected to said selected, predetermined line pairs and which are not then in use. 
     
     
       2. A multi-subscriber warning system as claimed in claim 1 wherein said telephone system has a distribution panel where conductors are appropriately connected together, wherein said manually-set, subscriber-selecting, connecting means is mounted on said distribution panel, and wherein said predetermined contacts of said plurality of contacts are connected to some of said conductors. 
     
     
       3. A multi-subscriber warning system as claimed in claim 1 wherein said isolating means is controlled within a building of a telephone company and is controlled by an employee of said telephone company. 
     
     
       4. A multi-subscriber warning system as claimed in claim 1 wherein all of said telephone instruments are adapted to have the ringers thereof actuated by one predetermined frequency, and wherein said source of ringing current supplies said one predetermined frequency. 
     
     
       5. A multi-subscriber warning system as claimed in claim 1 wherein said manually-set, subscriber-selecting, connecting means includes spaced-apart contacts and selectively-removable connectors that removably interconnect said spaced-apart contacts. 
     
     
       6. A multi-subscriber warning system as claimed in claim 1 wherein said isolating means connects said source of ringing current to a multiplicity of line pairs at substantially the same instant. 
     
     
       7. A multi-subscriber warning system as claimed in claim 1 wherein said isolating means connects said source of ringing current to a multiplicity of line pairs at substantially the same instant, wherein all of said telephone instruments are adapted to have the ringers thereof actuated by one predetermined frequency, and wherein said source of ringing current supplies said one predetermined frequency. 
     
     
       8. A multi-subscriber warning system as claimed in claim 1 wherein said telephone system has a distribution panel where conductors are appropriately connected together, wherein said manually-set, subscriber-selecting, connecting means is mounted on said distribution panel, wherein said predetermined contacts of said plurality of contacts are connected to some of said conductors, and wherein said manually-set, subscriber-selecting connecting means includes spaced-apart contacts and selectively-removable connectors that removably interconnect said spaced-apart contacts.